Progressive Bitstream Optimization in MIMO Channels Based on a Comparison between OSTBC and SM

We study the optimal design of the multimedia communication systems that employ open-loop multiple-input multiple-output (MIMO) techniques. We first analyze the behavior of the crossover point of the error probability curves for orthogonal space-time block codes (OSTBC) and spatial multiplexing (SM) with a zero-forcing receiver. It is proven that in the high signal-to-noise ratio (SNR) regime, for both the information outage probability and the uncoded bit error rate, as data rate increases, the crossover point for the error probability monotonically decreases, and the crossover point for the SNR monotonically increases. Those results can be exploited for the optimal transmission of multimedia progressive sources which need unequal target error rates or transmission data rates in their bitstream, we show that the computational complexity involved with the optimal space-time coding of a progressive bitstream can be simplified.